OpenAI
Medium
Software EngineerDesign a Hosted Notebook Platform
System Design
48
0
April 12, 2026
Scalability Interview Questions
Scalability questions test whether you can design systems that handle growing load without degrading performance.
Expect questions on horizontal vs vertical scaling, database sharding, data partitioning strategies, and capacity planning.
Interviewers look for awareness of bottlenecks, trade-offs between consistency and throughput, and practical experience with scaling patterns.
911Questions
163Companies
Easy 42 • Medium 378 • Hard 479Difficulty mix
Common scalability interview patterns
- Horizontal vs vertical scaling trade-offs
- Database sharding strategies (hash, range, geographic)
- Read replicas and write scaling
- Stateless service design for horizontal scaling
- Auto-scaling policies and capacity planning
- Data partitioning and rebalancing
Scalability interview questions
Filter and sort
Anthropic
Hard
Software EngineerDesign a low-latency ML inference API
ML System Design
39
0
September 6, 2025
Optiver
Hard
Software EngineerDesign low-latency trading infrastructure
System Design
40
0
December 5, 2025
OpenAI
Nan
Software EngineerDesign a distributed crossword fill solver
System Design
33
0
January 17, 2026
Rippling
Easy
Software EngineerDesign a news aggregator system
System Design
56
0
December 5, 2025
Uber
Medium
Software EngineerDesign a meeting scheduler and shopping cart
System Design
31
0
March 1, 2026
Anthropic
Hard
Software EngineerDesign a concurrent web crawler
System Design
41
0
September 6, 2025
Scale AI
Medium
Software EngineerDesign pipeline using classification and embedding services
ML System Design
56
0
December 8, 2025
DoorDash
Hard
Software EngineerDesign a resilient dasher payment system
System Design
46
0
September 6, 2025
Ramp
Medium
Software EngineerDesign a banking system with payments and merging
System Design
54
0
January 22, 2026
Together AI
Hard
Software EngineerDesign a GPU-aware pod scheduler
System Design
30
0
August 7, 2025
Mistral AI
Hard
Software EngineerBuild and design a Mistral RAG agent
ML System Design
36
0
September 6, 2025
Anthropic
Hard
Software EngineerDesign a GPU inference API
ML System Design
47
0
August 1, 2025
Confluent
Hard
Software EngineerDesign a temporary email service
System Design
42
0
July 27, 2025
Salesforce
Medium
Software EngineerDesign a configurable monthly API rate limiter
System Design
39
0
February 12, 2026
OpenAI
Hard
Software EngineerDesign a GPU credit system and scheduler
ML System Design
30
0
August 13, 2025
OpenAI
Hard
Software EngineerDesign a Slack-like real-time messaging system
System Design
45
0
February 12, 2026
Anthropic
Medium
Software EngineerOptimize HTTP requests for speed and limits
System Design
26
0
December 8, 2025
Netflix
Hard
Software EngineerDesign ads frequency capping service
System Design
23
0
July 17, 2025
Shopify
Hard
Software EngineerDesign a rare-book lending and returns system
System Design
43
0
July 16, 2025
Common mistakes in scalability discussions
- Jumping to scaling solutions before estimating actual load
- Ignoring the consistency implications of horizontal scaling
- Overlooking hot partition problems in sharding schemes
- Not considering the operational complexity of distributed systems
- Assuming vertical scaling is always simpler
How scalability questions are evaluated
Structured reasoning about load estimation and bottleneck identification matters most.
Show awareness of trade-offs rather than presenting a single solution.
Discuss failure modes and how the system degrades under extreme load.